Clean and check wheel bolt connection components, then protect against corrosion - AP40.10-P-4050-01A

Before mounting a wheel-and-tire assembly all the following operation steps must be carefully conducted.

When conducting additional cleaning work using emery cloth, wire brush, flat scraper, wheel hub cleaner or thread-cutting tools only the deposited corrosion and dirt layer may be removed. There must be no material removal from the component.

Damaged or deformed components must always be replaced. Any residue deposits of corrosion, contamination, material removal from components or damaged components prevent the necessary preload force being reached on the wheel bolts or wheel nuts, despite reaching the specified torque!

Otherwise the wheel-and-tire assembly may work its way loose from the vehicle thereby causing damage!

When using disk wheels, wheel spacers and wheel bolts or wheel nuts from other manufacturers, in which the wheel connection was not checked and approved by Daimler AG, Daimler AG shall then not be held liable.

Notify the customer about this accordingly.

Fig 1: Identifying Wheel And Tire Assembly Contact Surfaces Soiled With Grease

Courtesy of MERCEDES-BENZ USA

Fig 2: Identifying Corroded Contact Surface

Courtesy of MERCEDES-BENZ USA

Fig 3: Identifying Cleaned Contact Surface Of Wheel And Tire Assembly

Courtesy of MERCEDES-BENZ USA

1. Clean contact surface on wheel hub, wheel flange, brake disk or brake drum, center hole guide and joints for lubricants and soiling such as, e.g. oil, grease and sand.

   Use cleaner and rag.

2. Check contact surface on wheel hub, wheel flange, brake disk or brake drum, center hole guide and joints for deposited corrosion.

   If deposited corrosion is present, remove it using a wire brush or emery cloth or wheel hub cleaner, and then repeat operation step  1.

3. Check contact surface on wheel hub, wheel flange, brake disk or brake drum, center hole guide and joints for damage and deformation.

   If deformation or damage is present, replace affected components.

4. Check inside thread in wheel hub or wheel stud for soiling such as, e.g. oil, grease and sand and deposited corrosion.

   In the event of any soiling or deposited corrosion, remove it using a wire brush or thread cutter, and clean thread using cleaner.

5. Check inside thread in wheel hub or thread on wheel stud for signs of damage and deformation.

   If deformation or damage is present, replace affected components.

Fig 4: Identifying Cleaned And Uncleaned Surfaces Of Wheel And Tire Assembly
Courtesy of MERCEDES-BENZ USA
Fig 5: Identifying Radius Seat Not Cleaned
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Fig 6: Identifying Radius Seat Cleaned, Without Deformation And Scoring Marks
Courtesy of MERCEDES-BENZ USA
6. Check disk wheel and rim flanges for deformation and damage.

   In event of deformation or damage, replace disk wheel.

7. Clean contact surfaces and center hole guide for disk wheel of lubricants and soiling such as, e.g. oil, grease and sand.

   Use cleaner and rag.

8. Check contact surfaces and center hole guide on disk wheel for deposited corrosion.

   If deposited corrosion is found on the contact surfaces and center hole guide, clean them using a suitable tool (see above). Clean light alloy wheels using flat scraper and rags only. Then repeat operation step  7.

9. Check contact surfaces and center alignment on disk wheel for deformation and damage.

   In event of deformation or damage, replace disk wheel.

10. Check radius seats of disk wheels for soiling such as, e.g. oil, grease and sand.

    Clean radius seats with soiling using cleaner and rags.

11. Check radius seats of disk wheels for damage, scoring marks, corrosion, ring shaped material removal in circumferential direction and out-of-roundness.

    If radius seats exhibit damage, scoring marks, corrosion, material removal or out-of-roundness, replace disk wheel.

Fig 7: Identifying Corroded Spherical Cap
Courtesy of MERCEDES-BENZ USA
Fig 8: Identifying Spherical Cap With Seizing Marks, Material Deposition
Courtesy of MERCEDES-BENZ USA
Fig 9: Identifying Spherical Cap With Even Contact Pattern
Courtesy of MERCEDES-BENZ USA
12. Check thread of wheel bolts or wheel nut for soiling such as, e.g. oil, grease and sand, and deposited corrosion.

    In the event of any soiling or deposited corrosion, remove it using a wire brush or thread cutter, and clean thread using cleaner.

13. Check radius seats of wheel bolts or wheel nuts for soiling such as, e.g. oil, grease and sand, damage, scoring marks, corrosion, material removal and out-of-roundness.

    Clean radius seats with soiling using cleaner and rags. If radius seats exhibit damage, scoring marks, corrosion, material removal or out-of-roundness, replace wheel bolts or wheel nuts.

Fig 10: Applying Corrosion Protection To Wheel Hub
Courtesy of MERCEDES-BENZ USA
Fig 11: Applying Corrosion Protection To Wheel Flange
Courtesy of MERCEDES-BENZ USA
14. Apply a thin coating of hot lubrication paste as corrosion protection to the marked area of the center hole guide (arrow) on the wheel hub or wheel flange and wheel contact surface.

    Do not apply grease or other lubricants to threads of wheel bolts, wheel nuts, wheel hubs, wheel flanges or wheel studs.

    Otherwise the wheel-and-tire assembly may work its way loose from the vehicle thereby causing damage!